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tripmusic

macrumors 6502
Original poster
Oct 26, 2012
455
86
Switzerland
After much troubleshooting and a new PSU, it's looking like I have a bad motherboard. My CPU tray is already flashed from 4,1 to 5,1, so if I buy a 4,1 backplane board is it going to work? Would I be able to run the firmware tool again, so that the backplane board can be flashed? I was under the impression that the firmware tool changes the EFI of both the backplane and CPU tray. If that's the case, then I will have a conflict, as one is flashed and one is not.
 
After much troubleshooting and a new PSU, it's looking like I have a bad motherboard. My CPU tray is already flashed from 4,1 to 5,1, so if I buy a 4,1 backplane board is it going to work?
You need to buy a MP4,1 backplane or a MP4,1 backplane already upgraded to MP5,1 firmware.

A real MP5,1 backplane won't work with your tray since MP5,1 SMC firmware is 1.39f11 while MP4,1 SMC firmware is 1.39f5. Mismatched SMC between trays and backplanes makes all the case fans work at full RPM, full time.

The real problem is with Westmere Xeons, if you already upgraded your tray to one/two in the past. If you buy a MP4,1 backplane that was never flashed with MP5,1 firmware, you have to downgrade your Xeon(s) from Westmere back to Nehalem and then flash the BootROM to MP5,1. If you don't do the MP4,1 to MP5,1 flashing process, you can't use a Westmere Xeon since only MP5,1 firmwares support Westmere Xeons.

Would I be able to run the firmware tool again, so that the backplane board can be flashed?
Yes.
I was under the impression that the firmware tool changes the EFI of both the backplane and CPU tray. If that's the case, then I will have a conflict, as one is flashed and one is not.
CPU trays don't have BootROM firmware, just SMC firmware.

MP4,1 SMC firmware is not user or technician updatable, only Apple can update/downgrade SMC firmwares since it's a secure micro controller that needs a key to be updated, this key never leaved Apple possession. It's one of the few things that never leaked, right next to the MP4,1/MP5,1 electrical schematic.
 
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I have a spare 4,1 flashes to 5,1 that would work for you.
I appreciate the offer, however I'm in Europe, unless yo'd want to ship it there?
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You need to buy a MP4,1 backplane or a MP4,1 backplane already upgraded to MP5,1 firmware.

A real MP5,1 backplane won't work with your tray since MP5,1 SMC firmware is 1.39f11 while MP4,1 SMC firmware is 1.39f5. Mismatched SMC between trays and backplanes makes all the case fans work at full RPM, full time.

The real problem is with Westmere Xeons, if you already upgraded your tray to one/two in the past. If you buy a MP4,1 backplane that was never flashed with MP5,1 firmware, you have to downgrade your Xeon(s) from Westmere back to Nehalem and then flash the BootROM to MP5,1. If you don't do the MP4,1 to MP5,1 flashing process, you can't use a Westmere Xeon since only MP5,1 firmwares support Westmere Xeons.

Yes.

CPU trays don't have BootROM firmware, just SMC firmware.

MP4,1 SMC firmware is not user or technician updatable, only Apple can update/downgrade SMC firmwares since it's a secure micro controller that needs a key to be updated, this key never leaved Apple possession. It's one of the few things that never leaked, right next to the MP4,1/MP5,1 electrical schematic.
Thanks for all the info. I was aware about the SMC conflicts between mixing 2009 and 2010 hardware, but I wasn't sure if the BootRom was on the tray as well. My tray is a 2009. I should be fine then, as I've got my original Quad-core Xeon and can pop that in to do the flashing on another 4,1 backplane.
 
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What makes you think that you need a new backplane ?
It started a year or so ago. The SIL indicator light would remain solid, no matter if it was shutdown, powered on, or asleep. I also noticed the EFIDone diagnostic light was always flickering slightly when shutdown. Once booting, it becomes solid. I've made other posts about it with no answers and the machine was working just fine performance-wise regardless. Until now...

So recently, I noticed that when I would put it to sleep, I'd go to wake it and it had shutdown. Then, I started hearing relay clicking sounds when powering on and thought it must be the PSU on it's way, so I picked up a refurbished one. That didn't fix the problem. Now it won't turn on at all, even if I jumper the solder pads. I've run AHT and ASD and found no errors, but I've narrowed it down to the backplane, or possibly the CPU tray, but I don't think it's that. All the Caps on both boards look fine.

If I can find a decent deal on a whole 4,1 machine I may just do that, so I can rule out if my tray is bad. I'm in Switzerland though, so the shipping and customs fees become expensive, as most of the deals are coming from the US.
 
Clean the PSU with a compressor 60 PSI at 6 inches . Dust has been known to shut down cMPs . PSU is a component especially vulnerable due to a sealed relay that is susceptible to particulate contamination .

Before you go through the expensive ( both money and time ) of replacing the backplane board , borrow a CPU Tray from any 2009-12 Mac Pro - don't worry about the fan speed issue . We just want to verify your backplane is working .

What do your backplane board diagnostic LEDs currently look like, when you press the button ?

Mac Pro 4,1 and 5,1 ( Nehalem ) BackPlane Onboard LED Diagnostic Indicators :

Upper bank :

OVTMP CPUA
OVTMP CPUB
PSU PWROK
5V STBY
3.3V ( No light installed )
1.5V ( No light installed )
1.05V ( No light installed )


Lower bank :
SYS PG
PLT RS ( No light installed )
X1 PG ( No light installed )
EFI DONE
GPU OK
5V ( No light installed )
RSM RST ( No light installed )

During normal operation , the PSU PWROK is green , the 5V STBY is amber , the SYS PG is green and the EFI DONE is green . The GPU light might be different , depending on if you are using an EFI graphics card .
 
I’m on the same boat, got a 4.1 that was obviously flashed to 5.1 because i found a w5680 inside .
tryed a tray swap with my working 5.1 dual tray both of the machine not booting , blackscreen, fanspin, front led solid on.
swap back the tray my 5.1 boot normally, the 4.1 not.

tryied to drop a e5540 in the 4.1 tray with same result.

changed the clock battery, try jumping sys-pwr and smc-rst, with led diag :
cpu-pwr: green
5v : amber
gpu : green
 
Clean the PSU with a compressor 60 PSI at 6 inches . Dust has been known to shut down cMPs . PSU is a component especially vulnerable due to a sealed relay that is susceptible to particulate contamination .

Before you go through the expensive ( both money and time ) of replacing the backplane board , borrow a CPU Tray from any 2009-12 Mac Pro - don't worry about the fan speed issue . We just want to verify your backplane is working .

What do your backplane board diagnostic LEDs currently look like, when you press the button ?

Mac Pro 4,1 and 5,1 ( Nehalem ) BackPlane Onboard LED Diagnostic Indicators :

Upper bank :

OVTMP CPUA
OVTMP CPUB
PSU PWROK
5V STBY
3.3V ( No light installed )
1.5V ( No light installed )
1.05V ( No light installed )


Lower bank :
SYS PG
PLT RS ( No light installed )
X1 PG ( No light installed )
EFI DONE
GPU OK
5V ( No light installed )
RSM RST ( No light installed )

During normal operation , the PSU PWROK is green , the 5V STBY is amber , the SYS PG is green and the EFI DONE is green . The GPU light might be different , depending on if you are using an EFI graphics card .
As I said, I've already replaced the PSU and that didn't solve the problem. When the unit is plugged in and shutdown, the SIL is ON solid and the EFIDone flickers ever so slightly, which is odd... that's without pressing the diagnostics button. The SIL is only ON solid (and shutdown) when the CPU tray is installed. With the tray removed, the SIL is off, but the EFIDone light still flickers without pressing anything.

I have the unit gutted at the moment, but from memory, all of the above operation LEDs you mentioned are what mine displays when booting when pressing the diagnostics button. The only one I'm not positive about is the SYS PG. If I put it back together and it's able to boot (which is becoming unlikely), I'll check that LED to be sure.
 
I’m on the same boat, got a 4.1 that was obviously flashed to 5.1 because i found a w5680 inside .
tryed a tray swap with my working 5.1 dual tray both of the machine not booting , blackscreen, fanspin, front led solid on.
swap back the tray my 5.1 boot normally, the 4.1 not.

tryied to drop a e5540 in the 4.1 tray with same result.

changed the clock battery, try jumping sys-pwr and smc-rst, with led diag :
cpu-pwr: green
5v : amber
gpu : green
There's a difference between a 2009 that's been flashed to 5,1 and an actual 5,1 from 2010. They're not interchangeable because the SMC is different.

I've read that the refurbished 4,1's from Apple with the BootRom ending in B08, was a prototype and can actually run 6-core Xeons without flashing to 5,1.
 
There's a difference between a 2009 that's been flashed to 5,1 and an actual 5,1 from 2010. They're not interchangeable because the SMC is different.

I've read that the refurbished 4,1's from Apple with the BootRom ending in B08, was a prototype and can actually run 6-core Xeons without flashing to 5,1.


I purchased a 2009 4,1 that came stock with the B08 bootrom. That's not a prototype, it was on official brand new machines

The 4,1 B08 bootrom rumor (never heard this before) about booting Westmere CPUs sounds false to me
 
I can offer a 4.1 to 5.1 board, too. But I dont ship to switzerland, if the ts can use a shipping service to germany I can send a board.
 
I purchased a 2009 4,1 that came stock with the B08 bootrom. That's not a prototype, it was on official brand new machines

The 4,1 B08 bootrom rumor (never heard this before) about booting Westmere CPUs sounds false to me
Who knows? Maybe they revised the B07 FW and started shipping '09 MP's with it and then refurb's?
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I can offer a 4.1 to 5.1 board, too. But I dont ship to switzerland, if the ts can use a shipping service to germany I can send a board.
Thanks. I appreciate the offer
 
Who knows? Maybe they revised the B07 FW and started shipping '09 MP's with it and then refurb's?

I bought mine in 2010 actually so it was a few months prior to the 5,1 release. I believe the B08 firmware was the last 4,1 firmware to come stock from the factory. So yes, it would make sense that if any firmware work had to be done on repairs or refurbished units, they would have gotten B08 too since it was the "latest and greatest" at that time
 
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My CPU tray is already flashed from 4,1 to 5,1, so if I buy a 4,1 backplane board is it going to work? Would I be able to run the firmware tool again, so that the backplane board can be flashed?

You can't flash the tray, you only flashed the logic board.

Regardless you flashed your old logic board or not. If you want a logic board replacement, always buy the logic board that match your cMP's original ident. If that was a 4,1 originally, then get the 4,1 tray.

Your tray will able to work with the replacement 4,1 logic board, HOWEVER, the W3690 is not. You will need to swap the original CPU back in, flash your "new" logic board again, then re-install the W3690.
 
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You can't flash the tray, you only flashed the logic board.

Regardless you flashed your old logic board or not. If you want a logic board replacement, always buy the logic board that match your cMP's original ident. If that was a 4,1 originally, then get the 4,1 tray.

Your tray will able to work with the replacement 4,1 logic board, HOWEVER, the W3690 is not. You will need to swap the original CPU back in, flash you "new" logic board again, then re-install the W3690.
Yes, I have the original quad cpu for the 4,1, so that's not a problem.
 
tripmusic

I assume that you have alreaddy shutdown and done the THREE CONSECUTIVE CHIME NVRAM reset . .

Prior to that I would also remove all PCIe cards except your boot GPU . . . and even then put it in another PCIe slot eg: slot 4.

I would also remove ALL RAM modules & clean their contacts with a soft, clean eraser.

Finally, prior to doing the NVRAM reset I would remove the CMP's powr cord for 15 mins.

Good luck.
 
tripmusic

I assume that you have alreaddy shutdown and done the THREE CONSECUTIVE CHIME NVRAM reset . .

Prior to that I would also remove all PCIe cards except your boot GPU . . . and even then put it in another PCIe slot eg: slot 4.

I would also remove ALL RAM modules & clean their contacts with a soft, clean eraser.

Finally, prior to doing the NVRAM reset I would remove the CMP's powr cord for 15 mins.

Good luck.
Thanks. Yes I've done everything you mentioned. I wish I knew someone that had a 4,1 I could test my hardware with and narrow down whether it's the MoBo, or cpu tray. For all I know, whatever has corrupted this machine could've affected both. The flickering EFIDone light when the unit isn't even powered on and without the cpu tray in, tells me that the MoBo is definitely faulty. That diagnostic light should either be off, or on, correct? But also, the strange behavior of the always on, solid SIL light, only happens when the cpu tray is inserted. I'm gonna be on the lookout for a decent price on a stripped-down 4,1 machine. I'm in Switzerland, so the shipping and customs fees suck, as most of the deal are coming from the US.
 
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